Various types of magnetoresistive random access memory (MRAM) store data using magnetic tunnel junctions. A magnetic tunnel junction (MTJ) may include “fixed” and “free” magnetic layers, where a magnetic moment of the free layer may be switched to be parallel or antiparallel to a magnetic moment of the fixed layer. A thin dielectric or barrier layer may separate the fixed and free layers, and current may flow across the barrier layer due to quantum tunneling. A difference in resistance between parallel and antiparallel states allows data to be stored. For example, a low resistance may correspond to a binary “1” and a high resistance may correspond to a binary “0.” Alternatively, a low resistance may correspond to a binary “0” and a high resistance may correspond to a binary “1.”
Certain types of phase change memory (PCM) store data based on a phase of a material, such as chalcogenide. For example, an amorphous, high resistance state may represent a binary “0” and a crystalline, low resistance state may represent a binary “1.” Alternatively, an amorphous, high resistance state may represent a binary “1” and a crystalline, low resistance state may represent a binary “0.” There are certain conditions in which MRAM may be best to be used and some conditions in which PCM may be best to be used.